Fiber washing method and apparatus



C. L- COPELAND FIBER WASHING METHOD AND APPARATUS March 13, 1962INVENTOR.

El v

Clarence L. Copeland a .2 3 B 8% L13 a ml c e c e G c. a 1 G G E G G 2 yT 212.. 3:... M M m m vw Mm d H m n r|.E I w A n m 8 W; M 2 G G G G C Co w /w G E G G G G o 0 1 Z 4 1 I I l l I I I I I I I u I I v l l l I u I:3 4 m M m 5 mm m 1....h... w a A m H l w Q 0 IIIIL w\ Z 5 i! 3,fi25,2i3Patented Mar. 13, 1962 3,025,213 FIBER WASHHNG METHGD AND APPARATUSClarence L. Copeland, 565 N. H St, Aberdeen, Wash. Filed May 26, 1953,Ser. No. 737,676 Claims. (Cl. 162-4) This invention relates to methodand apparatus for washing fibrous materials.

The recovery of cellulosic fiber from waste newspapers, magazines, andlike sources presents a difiicult problem because of the diflicultyinherent in washing out and separating the small particles of printersink, paper-making filler and like materials which they contain. It istoward the solution of this problem that the present invention isdirected.

The manner in which the foregoing and other objects of this inventionare accomplished will be apparent from the accompanying specificationand claims, considered together with the drawings wherein like numeralsof reference indicate like parts, and wherein:

FIG. 1 is a plan view of apparatus employed in the presently describedfiber washing method;

FIG. 2 is a sectional view of the apparatus of FIG. 1, taken along line22 of that figure;

FIG. 3 is a fragmentary, detail view in section taken along line 33 ofFIG. 1; and

FIGS. 4 and 5 are detail views in front and side elevation,respectively, of a jet nozzle employed in the apparatus of theaforementioned figures.

Generally stated, the fiber washing method of my invention comprisesfirst suspending a mixture of fibrous material and foreign particlessuch as ink or papermakers filler in an aqueous medium. The resultingsuspension is introduced into a chamber, preferably the first of aplurality of chambers connected in series, where it is vigorouslyagitated.

After the particles have been dislodged from the fibers, to which theycling tenaciously, they are separated from the suspension by filteringthem through filter means the pores of which are dimensioned to pass theparticles but not the fibers. The processed suspension then istransferred to the next chamber of the series and thus passed fromchamber to chamber until the separation is complete and a fiber productis obtained which is suitable for reuse in papermaking processes.

Considering the foregoing in greater detail and with particularreference to the drawings:

In the illustrated embodiment, the herein described apparatus includes atank divided by transverse partitions 12, 14 into a number of chambers16, 18, 20, all connected in series. An aqueous slurry or suspension ofthe fibrous material to be cleaned and washed is introduced into thefirst of these chambers by suitable means, as through conduit 22provided with valve 23. It then passes through the chambers in sequence,flowing over the tops of partitions 12, 14 which are at a substantiallylower level than the top of the tank, and is discharged through anoverflow conduit 24, the flow through which is controlled by valve 25.

Although the fiber suspension introduced into the apparatus may bederived from a variety of sources and treatments, it preferablycomprises a suspension prepared by reducing newspapers, magazines, orother waste paper; suspending the reduced product in an aqueous mediumto form a suspension; and treating the suspension with a suitablechemical agent such as a detergent or alkaline material for breaking thebond between the foreign particles and the fibers.

Chambers 16, 18, 20 contain rotor assemblies 26, 28, so respectively,the construction of which may be substantially identical. Thus rotor 26comprises a hollow cylinder mounted on stub shafts 32, 34.

Shaft 32 is fixed to rotor 26 and is journalled in bearing 36. it isdriven at the selected operating speed through belt it) from motor 42.Rotor units 28, 30 are driven from the same power source through belts44, 46.

Shaft 34- is stationary so that rotor 26 turns freely about it. It ismounted in flange 48 and is hollow forming a conduit communicating withanother conduit 50. Where, as illustrated, there are a number of washingchambers in series with each other, similar conduits 52, 54 are providedemanating from the rotor in each chamber and communicating with conduit50 the flow through which is controlled by valve 51.

T he periphery of rotor 26 is formed with a plurality of spaced, radialports 56 which are covered over with a Copper screen 58 or otherreticular member. The mesh size of the screen is such as to pass thefine particles of ink, filler or other foreign material present in thesuspension, but to restrain the fibers.

Agitating means are mounted on the rotor for vigorously agitating thesuspension contained in the chamber. Such means may comprise a pluralityof angularly formed blades 60 mounted at spaced intervals longitudinallyof the rotor by means of bolts 62. Spacing elements 64 preferably areincluded in the assembly to separate the blades from the periphery ofthe rotor. As a consequence, a flow of liquid is induced between theblades and the rotor surface which continuously washes the latter freeof fiber particles which otherwise might accumulate thereon and plugscreen 58.

Cooperating with blades 60 on rotor 26 are lower and upper arcuateplates 66, 68. These are concentric with the rotor and form, in effect,segments of a pump housing in which blades 60 act as impellers, creatinga fluid flow in a clockwise direction as indicated by the arrows of FIG.2.

Plate 66 may be welded between partition 12 and the bottom of tank 10.Plate 68 is preferably formed as a segment of a vertical plate 70 whichserves also as a baffle to divide the flow of fluid. Thus While themajor proportion of the fluid suspension travels in a circular path withthe rotor, a minor but substantial proportion of it is directed upwardlyby the baflle so that it passes over the top of partition 12 into thenext washing chamber.

The turbulence in the suspension produced by the action of blades 66 ismaterially augmented by fluid jet assemblies directed toward the regionbelow the rotor. There preferably are two such jet assemblies: an upperassembly fed, for example, with a mixture of air and water through 'aconduit 72 in which are mounted a plurality of jet nozzles 74, and alower assembly including a conduit 76 provided with spaced nozzles 77,which may be identical in construction with nozzles 74-. Both of theseassemblies direct fluid at high velocity to the region below the rotor,causing a condition of great turbulence which effectively dislodges thesmall foreign particles from the fibers.

Although the jet nozzles may assume a diversity of configurations, aconfiguration such as that illustrated in FIGS. 4 and 5 is preferred.Thus each nozzle may comprise a threaded section 7 8, a nut section 80and a nozzle section 82. The latter is so formed that the stream offluid passing through the body of the nozzle strikes the flat, angledundersurface 84 of the nozzle head and is converted to a fiat stream ofconsiderable velocity.

Operation The operation of the herein described fiber washing apparatusis as follows:

A waste paper slurry which may or may not first have been subjected to achemical treatment for loosening the particles of ink and clay or otherfiller present in the paper. is introduced into chamber 16 at acontrolled rate of flow. Cylindrical rotors 26, 28, 30 are driven at auniform rate by motor 42. Thereupon a vigorous agitation of thesuspension occurs, induced by the pumping action of angled blades 60within housing segments 66, 68.

At the same time, the jet action of the fluid streams discharged fromconduits 72, 76 through nozzles 74, 77 augments the turbulent condition.As a consequence the small particles of ink and size effectively arewashed off the fibers. Also, the accumulation of a fibrous deposit onthe surface of the rotor is prevented by the effect of the jet streamsacting through the spacing present between blades 60 and the surface ofthe rotor.

Valve 51 is so adjusted that a gravitational flow of liquid occursthrough screen 58, ports 56, the hollow interior of cylindrical rotor26, conduit 34 and conduit 50. This flow carries with it the smallparticles of ink and size, leaving behind the fibers.

As rotor 26 revolves, the fluid flow induced thereby is divided bybaflie 70 so that a major proportion, for example about of thesuspension, is carried around beneath housing segment 68, and a minorbut substantial proportion, for example, about A of it, passes upwardlybetween baffle 70 and partition 12. It thereupon passes over the top ofthe partition and into chamber 18 where it is further treated by theaction of rotor 28 which has an action similar to that of rotor 26.

The suspension processed in chamber 18 may be passed to chamber 20 andprocessed in a similar manner, there being as many chambers connected inseries with each other as may be required for effective treatment of thefiber. The overflow from the final chamber passes out through dischargeconduit 24. The adjustment of valve in this conduit is correlated withthat of valve 23 in feed conduit 22 and valve 51 in discharge conduit 50so that the fluid in the treating tank is maintained at working level atall times.

Thus it will be apparent that by the present invention I have providedmethod and apparatus for washing fibrous material to free it from smallparticles of foreign matter such as ink and filler. The apparatus isoperable at a high production rate and is not subject to plugging by thefibrous material, which has been a serious deficiency of washing unitsof the prior art. Also, it separates the foreign particles from thefibers with minimum loss of fiber fines. Still further, a fibrousproduct is obtained in high yield, substantially free of ink and fillerand well suited for use as a raw material in various papermakingprocedures.

It is to be understood that the form of my invention herein shown anddescribed is to be taken as a preferred example of the same and thatvarious changes in the shape, size and arrangement of parts may beresorted to without departing from the spirit of the invention or thescope of the subjoined claims.

Having thus described my invention, I claim:

1. Fiber washing apparatus comprising a chamber, means for introducinginto the chamber an aqueous suspension of fibers and foreign particles,a hollow rotor mounted for rotation within the chamber,suspensionagitating means mounted on the periphery of the rotor, aplurality of ports opening out on the periphery of the rotor andcommunicating with the hollow interior thereof, conduit means connectedto the hollow interior of the rotor, filter means positioned across theports dimensioned to pass the foreign particles to the conduit meanswhile retaining the fibers, means adjacent the rotor providing a fluidjet directed substantially tangent to the rotor, and discharge means inthe chamber for discharging the washed suspension therefrom.

2. The fiber washing apparatus of claim 1 wherein thesuspension-agitating means and the fluid jet providing means comprise aplurality of blades placed longitudinally of the rotor a spaced distancefrom the periphery thereof.

3. Fiber washing apparatus comprising a chamber, means for introducinginto the chamber an aqueous suspension of fibers and foreign particles,a hollow rotor mounted for rotation within the chamber, a plurality oflongitudinal blades mounted a spaced distance from the periphery of therotor and serving to agitate the suspension with the rotation thereof,jet means positioned for directing a fluid jet stream substantiallytangent to the rotor thereby separating the foreign particles from thefibers and washing the fibers away from the rotor, a plurality of portsopening out on the periphery of the rotor and communicating with thehollow interior thereof, conduit means connected to the hollow interiorof the rotor, filter means positioned across the ports and dimensionedto pass the foreign particles to the conduit means while retaining thefibers, and discharge means communicating with chamber for removing thewashed fiber suspension therefrom.

4. Fiber washing apparatus comprising a chamber, means for introducinginto the chamber an aqueous suspension of fibers and foreign particles,a hollow rotor mounted for rotation within the chamber, a plurality ofspaced parallel blades mounted on the periphery of the rotorlongitudinally thereof for agitating the suspension, arcuate platesspaced from the periphery of the rotor and concentric therewith, fluidjet means positioned for directing a fluid stream to the area betweenthe plates substantially tangent to the rotor, thereby separating theforeign particles from the fibers and washing the fibers away from therotor, a plurality of ports opening out on the periphery of the rotorand communicating with the hollow interior thereof, conduit meansconnected to the hollow interior of the rotor, filter means positionedacross the ports dimensioned to pass the foreign particles to theconduit means and to retain the fibers, and discharge means for removingthe washed suspension of fibers from the chamber.

5. Fiber washing apparatus comprising a tank; a plurality of chambersplaced side by side within the tank and separated from each other bypartitions having a height less than that of the tank; means forintroducing an aqueous suspension of fibers and foreign particles intoone end chamber of the tank; in each chamber a suspension-cleaningassembly including a rotatably mounted hollow cylinder,suspension-agitating means mounted on the periphery of the cylinder,means adjacent the cylinder providing a fluid jet directed substantiallytangent to the cylinder, a plurality of ports opening out on theperiphery of the cylinder and communicating with the hollow interiorthereof, conduit means connected to the hollow interior of the cylinder,and filter means positioned across the ports dimensioned to pass theforeign particles to the conduit means and to retain the fibers; anddischarge means for removing the washed suspension from the lastsucceeding chamber; the means for introducing the suspension into thetank being coordinated with the discharge means and the filter means sothat a portion of the fibrous suspension passes over the partitionsseparating the chambers successively for further processing in eachchamber and the remaining portion of the fibrous suspension is recycledthrough the preceding chamber.

References Cited in the file of this patent UNITED STATES PATENTS685,593 Franklin Oct. 29, 1901 1,389,281 Winestock Aug. 30, 19211,904,066 McAIthur Apr. 18, 1933 1,960,106 Grewin May 22, 1934 2,083,884Wells June 15, 1937 2,355,243 Scheid Aug. 8, 1944 2,442,990 Wells June8, 1948 2,546,247 Wolf Mar. 27, 1951 2,916,216 Altmann Dec. 8, 1959

1. FIBER WASHING APPARATUS COMPRISING A CHAMBER, MEANS FOR INTRODUCINGINTO THE CHAMBER AN AQUEOUS SUSPENSION OF FIBERS AND FOREIGN PARTICLES,A HOLLOW ROTOR MOUNTED FOR ROTATION WITHIN THE CHAMBER,SUSPENSIONAGITATING MEANS MOUNTED ON THE PERIPHERY OF THE ROTOR, APLURALITY OF PORTS OPENING OUT ON THE PERIPHERY OF THE ROTOR ANDCOMMUNICATING WITH THE HOLLOW INTERIOR THEREOF, CONDUIT MEANS CONNECTEDTO THE HOLLOW INTERIOR OF